07/18/2022 | Drinking Water | 8 MINUTE READ

EPA Contaminants of Emerging Concern in Drinking Water


Many of the contaminants that can get into water are currently regulated by the Environmental Protection Agency, which means that water treatment facilities are tasked with making sure that contaminant levels are low enough for the water to be safe to drink. For instance, drinking water regulations state than fluoride levels must be at 2.0 mg/L or less to be safe. Measurement methods and reporting requirements are wll documented, inlcuding ion selective electrode techniques. While the Environmental Protection Agency has long been focused on making sure that contaminants in water are properly regulated, not every potential contaminant has been regulated.

There are many emerging contaminants that the EPA is concerned about, which extends to chemicals from medicines, household cleaning products, and personal care products. The main issue with contaminants that have yet to be regulated is that water treatment facilities and industrial plants may send out water that hasn’t been properly filtered. Even if regulated contaminants have been removed from the water, the presence of unregulated contaminants could create issues with overall water quality.

The primary concern that the EPA has in regards to unregulated contaminants involves drinking water contaminants. Since facilities that produce drinking water are required to test for regulated contaminants, people can be confident that the water they’re drinking only contains minimal amounts of these contaminants.

On the other hand, unregulated contaminants can’t be easily measured for and don’t need to be removed from the water before distribution, which may result in people drinking water that could make them sick. This article offers a comprehensive guide on EPA contaminants that are of emerging concern.


EPA Unregulated Contaminants Concerns

Because of how contaminants reduce the drinking water supply that people have access to, the Environmental Protection Agency has created an extensive amount of regulations to ensure that the majority of contaminants are properly controlled. The purpose of these regulations is to reduce the cosmetic and aesthetic effects that various contaminants can cause. The following is a list of the main contaminants that are regulated by the EPA:

  • Aluminum – 0.05-0.2 mg/L
  • Chloride – 250 mg/L
  • Color – 15 color units
  • Copper – 1.0 mg/L
  • Corrosivity – Fully non-corrosive
  • Fluoride – 2.0 mg/L
  • Foaming agents – 0.5 mg/L
  • Iron – 0.3 mg/L
  • Manganese – 0.05 mg/L
  • Odor – A threshold odor number of 3.0
  • pH levels – 6.5-8.5
  • Silver – 0.10 mg/L
  • Sulfate – 250 mg/L
  • Total dissolved solids – 500 mg/L
  • Zinc – 5 mg/L

In addition EPA continues to evaluate emerging pollutants of concern. The EPA web site provides fact sheets on these, including sources, detection, and known impacts. As our understanding of the impacts of these pollutants evolves, EPA may make additional recommendations of regulations.

What Is the EPA Worried About When it Comes to Drinking Water?

At the moment, the Environmental Protection Agency has emerging concerns about unregulated contaminants in drinking water. These contaminants typically refer to different types of chemicals, which extend to agricultural products, cleaning products, medicines, and personal care products. Because of how often these chemicals are used, it’s common for them to seep into lakes and rivers, which damages aquatic ecosystems.

Eventually, some fish become contaminated which leads to bioaccumulation within the food web. The aquatic species that eat other contaminated fish will also become contaminated. At the moment, the USGS monitors rivers and lakes to identify these chemicals and attempt to find the original source.

Once contaminants enter streams and rivers, measurements indicate that high levels of contaminants are present in the water as well as any underwater sediments. It’s also been found that the fish and aquatic insects that live in these waters will eventually become contaminated as well. The contaminants that are of emerging concern to the EPA get into the environment on a daily basis.

When chemicals from cleaning products and agricultural products get into water or wastewater, they tend to remain in the water even after treatment since the majority of treatment plants aren’t capable of getting rid of these chemicals. The industrial facilities that use some of these chemicals may not have the treatment processes needed to get rid of these chemicals.


Since these chemicals have yet to be regulated by the EPA, there’s no reason for industrial or water treatment facilities to remove them from water. Most industrial facilities will send their treated wastewater into the environment once it’s been treated. If chemicals still remain in the water following treatment, the water will then be affecting the environment. The risk that these contaminants have to humans is still not fully understood.

Studies of groundwater resources that are used to produce drinking water throughout the U.S. have indicated that this water isn’t necessarily susceptible to being contaminated by pharmaceuticals or hormones and that any detectable levels of these chemicals aren’t high enough to cause long-lasting health issues. The issues with these studies is that the data is relatively limited. It’s also been suggested that the chemicals that are most likely to be found in drinking water are high in solubility and are common in wells that only contain small amounts of groundwater.

When you’re attempting to identify contaminant levels in your water, it’s important that you obtain the proper measurements. There are many powerful water quality sensors that can help you determine which contaminants are present in a water sample and what the current contaminant levels are. The most common water quality sensors available for you to select from include pH sensors, conductivity sensors, dissolved oxygen sensors, and oxidation reduction potential sensors.

A pH sensor tells you if the water is currently alkaline or acidic. Clean and filtered water will have a pH of around 6.5-7.5. Acidic water ranges from 0-7pH, while alkaline water ranges from 7-14pH. High concentrations of minerals like calcium and magnesium will cause a water’s pH to increase. On the other hand, contaminants like ammonia, aluminum, and other metals can lead to a decrease in pH levels.

How Are These Contaminants Being Produced?

Water is highly susceptible to becoming contaminated from a wide range of different sources, which is why water usually needs to be treated before it’s potable. The seven primary sources of water pollution extend to:

  • Industrial waste
  • Wastewater
  • Marine dumping
  • Agriculture
  • Oil spills
  • Radioactive waste
  • Global warming

Industrial facilities are among the main contributors to water contamination. During standard operations, these facilities produce a certain amount of waste via toxic pollutants and chemicals. This waste needs to be treated before being sent into a freshwater system. However, some facilities don’t properly treat wastewater before disposing of it, which can lead to pollution. Industrial waste can also get into streams and rivers from mines and agricultural sites.

When looking at standard wastewater and sewage, this water can consist of chemicals, pathogens, and bacteria that are harmful to humans and the environment. As for marine dumping, this occurs when garbage is dumped directly into ocean waters. Many countries use this method to dispose of household garbage. Keep in mind that some items can take centuries to decompose.


In agriculture, many farmers use pesticides and chemicals to make sure that insects and bacteria don’t damage crops. These chemicals can get into groundwater and create health issues with plants, humans, and animals. Keep in mind that this contaminated water may also become mixed with rainwater, which will eventually flow into streams and rivers to further pollute important sources of water.

Oil spills aren’t exactly common but are still a major source of water pollution. A single oil spill can lead to the loss of more than 100 million gallons of oil, which substantially pollute nearby waters.

Radioactive waste is produced from facilities that are tasked with making nuclear energy. This waste needs to be properly disposed of since uranium is exceedingly toxic. As for global warming, rising temperatures invariably kill aquatic animals. If a considerable amount of these animals die off, water supplies can become highly polluted.

Possible Solutions for EPA Contaminants in Drinking Water

There are several ways to eliminate water contaminants and make sure that EPA guidelines are properly met. Among the most effectively solutions involves the ion-exchange process, which uses special equipment that’s outfitted with a micro-porous resin. A solution is placed on the resin before the water treatment process begins.

Once water is sent into the resin bed, ions within the water become attached to the resin beads, which results in the solution being sent into the water. This process allows harmless components in the solution to be exchanged for contaminants in the water, which means that contaminants will slowly accumulate on the resin. Keep in mind that the exchange resin should be cleaned regularly to remove the contaminants and maintain efficacy.


Another potential treatment involves activated carbon filtration, which is able to get rid of dioxins, radioactive wastes, PCBs, and fuel from water. All chemicals in the water will become stuck on the filter, which means that only clean water gets through. Many fish tank filers and tap water filters are activated carbon filters. Just like ion-exchange filters, activated carbon filters must also be cleaned regularly. It’s common for activated carbon filters to be combined with other water treatments to ensure that many different types of contaminants are removed from the water.

Regardless of the type of water you would like to remove contaminants from, getting rid of some of the contaminants that have yet to be regulated by the EPA is highly recommended. By taking a proactive approach, you can eliminate any harmful contaminants and provide yourself or your facility with clean and healthy water.

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Posted by Dominic O'Donnell on July 18, 2022

Sensorex is a global leader in the design and manufacture of quality sensors for water quality and process applications. The company offers more than 2000 sensor packages for pH, ORP, conductivity, dissolved oxygen, free chlorine, chlorine dioxide, UV transmittance and other specialty measurements, as well as a full line of sensor accessories and transmitters. Its expert technical support engineers solve analytical sensor challenges with custom designs and off the shelf products.

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